Radio waves are electromagnetic waves that can be used in wireless communication. The frequencies of these waves serve as physical communication channels. The radio frequency (RF) spectrum has a finite range of frequencies, and thus a limited number of channels. In the United States, for example, the Federal Communications Commission (FCC) decides how the spectrum is allocated and what bands are used for what purpose. Communication signals on the same channel interfere, assuming the strengths of the signals are non-negligible due to transmission power and distance. Also, communication signals on adjacent channels may interfere with communications on the desired channel because of inadequate filtering, tuning or frequency control. Adjacent channel interference can increase with an increase in signal power in adjacent channels.
Most countries of the world have allocated certain frequency spectrums for commercial use as “unlicensed” wireless bands. For example, the FCC has designated license-free bandwidth segments for industrial, scientific and medical (ISM) uses. Various commercial applications use this unlicensed bandwidth for short range wireless communication. Channels are not allocated within the license-free band. Commercial devices designed to operate in the license-free band are constrained to transmit using a relatively low power, which allows more commercial devices to use the unlicensed frequency bands by increasing the reuse of a frequency.
Furthermore, not only may a number of commercial devices be operating within a communication band, but also more than one wireless technology may co-exist within the communication band. For example, the 2.4 GHz band includes wireless LAN, Bluetooth and IEEE 802.15.4 technologies. Wireless LAN, falling under the 802.11b and 802.11g standards, has three non-overlapping channels with a bandwidth of 22 MHz. Subsequent revisions on the 802.11 standard has increased the wireless LAN bandwidth above 22 MHz. Bluetooth technology has 79 channels each with a bandwidth of 1 MHz, Bluetooth low energy technology has 40 channels each with a bandwidth of 2 MHz, and IEEE 802.15.4 has 11 channels with a bandwidth of 5 MHz. Wireless communication devices attempt to select adequate channels through which to communicate within this environment. For example, AFH (adaptive frequency hopping) may be used to select adequate channels based on both RSSI (Received Signal Strength Indication) noise measurements and based on retransmission attempts.
Signal attenuation and interference sources can impact wireless link quality. Wireless link quality may be further degraded if the wireless signal source, such as a phone, is in a person's pocket and/or is operating in a non-multi-path environment. The degraded wireless link quality may cause the person to experience overall degraded performance.
Wireless propagation is statistical in nature. The wireless link quality may vary drastically from individual to individual and from environment to environment. Some people may not experience significant degradation in link quality whereas others may experience significant link quality degradations. Furthermore, environmental variables may impact the degradation in performance experienced by the person, but the source of the degradation may not be intuitively known to the user. In an effort to statistically improve link performance, some manufacturers specify that the wireless signal source (e.g. phone) should be placed in specific locations. However, this does not educate the end customer to optimize the link quality.
Data may be collected on a phone and then later transferred the data to a location in the cloud for retrieval and analysis by a computer utility. However, this process is not efficient for the end customer. RSSI has been used for different applications to provide a measure of the power present in a received signal. However, the end user does not access the RSSI if the phone is in the pocket.
Accordingly, there is a need in the art for improving wireless communication to assist the end user in diagnosing and solving link quality problems.